352. Monosyllabic stems in composition. When the nouns above described occur as a final member of a compound, or when any root in ā or ī or ū is found in a like position, the inflection of an ā-stem is as above. But ī- and ū-stems follow a divided usage: the final vowel before a vowel-ending is either converted into a short vowel and semivowel (iy or uv, as above) or into a semivowel simply (y or v). The accent is nowhere thrown forward upon the endings; and therefore, when ī and ū become y and v, the resulting syllable is circumflex (83–4). Thus: